Compressors which compress a refrigerant have been known. Japanese Unexamined Patent Publication No. 2010-285930 discloses a scroll compressor of this type.
In the compressor disclosed in Japanese Unexamined Patent Publication No. 2010-285930, a motor is fixed to an inner surface of a casing, and a drive shaft is coupled to the motor. A scroll-type compression mechanism is coupled to an upper portion of the drive shaft. In the compression mechanism, a movable scroll eccentrically rotates about a fixed scroll, and a refrigerant in a compression chamber is thereby compressed.
In this compressor, oil in an oil reservoir at the bottom of the casing is supplied to a pin bearing and an upper main bearing which are positioned above the motor, through an oil supply path in the drive shaft during a compression operation to lubricate the sliding portion thereof. After lubrication, the oil is discharged to the outside of the housing, and guided into a gap between the casing and a core cut formed in the outer circumferential surface of a stator of the motor via an oil return guide, and the oil drops from the lower end of the gap and is discharged into the oil reservoir.